"""Explicit USB-only smoke test: request a fixed sentence, then hang up."""
import argparse
import time
import serial

p = argparse.ArgumentParser()
p.add_argument("--port", default="COM6")
p.add_argument("--seconds", type=int, default=60)
args = p.parse_args()
port = serial.Serial()
port.port, port.baudrate, port.timeout = args.port, 115200, 0.2
port.dtr = port.rts = False
port.open()
markers = ("PLATFORM_HTTP", "Platform error code:", "call_client:", "USB diagnostic:",
           "RTC", "rtc", "volc_start", "PLAYBACK", "DOWNLINK", "AUDIO conversation", "on_volc", "rst:",
           "panic", "Rebooting", "assert failed", "Guru Meditation", "conv_ai_service", "ERR|", "volc_conv.c",
           "Backtrace", "PC      :", "EXCVADDR", "A0      :", "Core  1 register")
try:
    print("Starting explicit USB test conversation", flush=True)
    port.write(b"diag-say\n")
    started = time.monotonic()
    stopped = False
    diagnosed = False
    while time.monotonic() - started < args.seconds:
        if not diagnosed and time.monotonic() - started >= 10:
            port.write(b"diag-state\n")
            diagnosed = True
        if not stopped and time.monotonic() - started >= args.seconds - 15:
            port.write(b"diag-stop\n")
            stopped = True
            print("Requested hangup", flush=True)
        line = port.readline().decode(errors="replace").strip()
        if line and any(m in line for m in markers):
            print(line, flush=True)
finally:
    if not stopped:
        port.write(b"diag-stop\n")
    port.close()